Abstract

EFFECT OF VARIOUS ADDITIVES (LIME WATER AND SALINE) ON THE PHYSICAL PROPERTIES OF PLASTER OF PARIS IN ORTHOPAEDIC PRACTICE

Patrick Ugochukwu Agbasi * Osinachi Chidera Amuta Onyinye Ure Ihekandu

ABSTRACT

Background: Plaster of Paris is used in medicine, arts and construction industry. And the problems associated with plaster of Paris includes increased time to set, water permeability and strength/hardness. Purpose: this research is undertaking therefore to assess the effect of lime water and saline on the physical properties/indices of Plaster of Paris (POP). Methods: The standard mixing ratio for POP and water is two parts of POP to one part of water by weight which was used as control. 25%, 50% and 100% saline were used to mix the POP. The same procedure was repeated with lime water and all the samples (test and control) were allowed to set for 5 days at room temperature. Results: showed that the bulk densities of 25% saline, 25% lime water and 50% lime water were significantly reduced when compared with control. The bulk density of 50 and 100% saline were significantly increased compared with control. There is also dose dependent decrease between 50% and 100% saline. The Apparent porosities of 50% and100% saline, 100% lime water were significantly increased but 25% saline, 25% and 50% lime water were significantly reduced compared to control. The hardness of 25% lime water was significantly increased while that of 100% lime water and 50% saline were significantly reduced compared to control. The values for 50% and 100% lime water and also 25% saline were not significantly affected. There is dose dependent reduction between 25 and 50% lime water when compared with 100% lime water. Conclusion: in the light of the above, addition of lime water in Plaster of Paris preparation will provide additional strength, decrease water permeability and at the same time, reduce its bulk density. All these advantages will improve casting in orthopaedic cases and construction industry.

Keywords: Plaster of Paris, Lime water, Saline, Apparent porosity, Bulk density.